This is ffe.info, produced by makeinfo version 4.8 from ffe.texi. INFO-DIR-SECTION Utilities START-INFO-DIR-ENTRY * ffe: (ffe). Flat File Extractor. END-INFO-DIR-ENTRY This file documents version 0.2.3 of `ffe', a flat file extractor. Copyright (C) 2007 Timo Savinen Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Permission is granted to copy and distribute translations of this manual into another language, under the above conditions for modified versions.  File: ffe.info, Node: Top, Next: Overview, Prev: (dir), Up: (dir) ffe *** This file documents version 0.2.3 of `ffe', a flat file extractor. Copyright (C) 2007 Timo Savinen Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Permission is granted to copy and distribute translations of this manual into another language, under the above conditions for modified versions. * Menu: * Overview:: Preliminary information. * Samples:: Samples using `ffe'. * Invoking ffe:: How to run `ffe'. * ffe configuration:: How `ffe' works. * Problems:: Reporting bugs.  File: ffe.info, Node: Overview, Next: Samples, Prev: Top, Up: Top 1 Preliminary information ************************* The `ffe' program is a used to extract fields from flat files and to print them in different formats. The input file structure and printing definitions are defined in a configuration file, which is always required. Default configuration file is `~/.fferc' (`ffe.rc' in windows). `ffe' is a command line tool developed for GNU/Linux and UNIX systems. `ffe' can read from standard input and write to standard output, so it can be used as a part of a pipeline. There is also binary distribution for windows.  File: ffe.info, Node: Samples, Next: Invoking ffe, Prev: Overview, Up: Top 2 Samples using `ffe' ********************* One example of using `ffe' for printing personnel information in XML format from fixed length flat file: $ cat personnel john Ripper 23 Scott Tiger 45 Mary Moore 41 $ A file `personnel' contains three fixed length fields: `FirstName', `LastName' and `Age', their respective lengths are 9,13 and 2. In order to print data above in XML, following configuration file must be available: $cat personnel.fferc structure personel { type fixed output xml record person { field FirstName 9 field LastName 13 field Age 2 } } output xml { file_header "\n" data "<%n>%t\n" record_header "<%r>\n" record_trailer "\n" indent " " } $ Using ffe: $ffe -c personnel.fferc personnel john Ripper 23 Scott Tiger 45 Mary Moore 41 $  File: ffe.info, Node: Invoking ffe, Next: ffe configuration, Prev: Samples, Up: Top 3 How to run `ffe' ****************** `ffe' is a command line tool. Normally `ffe' can be invoked as: `ffe -o OUTPUTFILE INPUTFILE...' `ffe' uses the definitions from configuration file and tries to guess the input file structure using the first 10 000 lines or 1 MB of input data. If the structure cannot be guessed the option `-s' must be used. * Menu: * Invocation:: Program invocation * Configuration:: Input and printing definitions * Guessing:: How ffe identifies input structure * Limits:: Limitations  File: ffe.info, Node: Invocation, Next: Configuration, Up: Invoking ffe 3.1 Program invocation ====================== The format for running the `ffe' program is: ffe OPTION ... `ffe' supports the following options: `-c FILE' `--configuration=FILE' Configuration is read from FILE, instead of `~/.fferc' (`ffe.rc' in windows). `-s STRUCTURE' `--structure=STRUCTURE' Use structure STRUCTURE for input file, suppresses guessing. `-p OUTPUT' `--print=OUTPUT' Use output format OUTPUT for printing. If not defined, then the record or structure related output format is used. Printing can be suppressed using format NO. `-o FILE' `--output=FILE' Write output to FILE instead of standard output. `-f LIST' `--field-list=LIST' Print only fields and constants listed in comma separated list LIST. Order of names in LIST defines also the printing order. `-e EXPRESSION' `--expression=EXPRESSION' Print only those records for which the EXPRESSION evaluates to true. `-a' `--and' Expressions are combined with logical and, default is logical or. `-v' `--invert-match' Print only those records which don't match the expression. `-l' `--loose' Normally `ffe' stops when it encounters an input line which doesn't match any of the records in selected structure. Defining this option causes `ffe' continue despite the error. `-r' `--replace=FIELD=VALUE' Replace FIELDs contents with VALUE in output. VALUE can contain same directives as output option `data'. `-?' `--help' Print an informative help message describing the options and then exit successfully. `-V' `--version' Print the version number of `ffe' and then exit successfully. All remaining options are names of input files, if no input files are specified or `-' is given, then the standard input is read. Expressions (option `-e', `--expression') ----------------------------------------- Expression can be used to select specific records comparing field values. Expression has syntax FIELD*x*VALUE, where *x* is the comparison operator. Expression is used to compare field's contents to VALUE and if comparison is successful the record is printed. Several expressions can be defined and at least one must evaluate to true in order to print a record. If option `-a' is defined all expressions must evaluate to true. If VALUE starts with string `file:' then the rest of VALUE is considered as a file name. Every line in file is used as VALUE in comparison. Comparison evaluates true if one or more values matches, so this makes possible use several different values in comparison. *Note*: The file size is limited by available memory because the file contents is loaded to memory. Expressions can be defined as: FIELD*=*VALUE Field FIELD is equal to VALUE. FIELD*^*VALUE Field FIELD starts with VALUE. FIELD*~*VALUE Field FIELD contains VALUE. FIELD*!*VALUE Field FIELD is not equal to VALUE. FIELD*?*VALUE Field FIELD matches the regular expression VALUE. `ffe' supports POSIX extended regular expressions.  File: ffe.info, Node: Configuration, Next: Guessing, Prev: Invocation, Up: Invoking ffe 3.2 Configuration ================= `ffe' uses a configuration file in order to read the input file and print the output. Configuration file for `ffe' is a text file. The file may contain empty lines. Commands are case sensitive. Comments begin with the `#'-character and end at the end of the line. The `string' definitions can be enclosed in double quotation `"' characters. `char' is a single character. `string' and `char' can contain following escape codes: `\a', `\b', `\t', `\n', `\v', `\f', `\r', `\"' and `\#'. A backslash can be escaped as `\\'. Configuration has two main parts: the structure, which defines the input file structure and the output, which defines how the input data is formatted for output. Common syntax ------------- Common syntax for configuration file is: #comment const NAME VALUE ... structure NAME { option value ... ... record NAME { option value ... ... } record NAME { option value ... ... } ... } structure NAME { ... } ... output NAME { option value ... ... } output NAME { ... } ... lookup NAME { option value ... ... } lookup NAME { ... } ... Structure --------- Keyword `structure' is used to define an input file content. An input file can contain several types of records (or lines). E.g. file can have a header, data and trailer record types. Records must be distinguishable from each other, this can be achieved defining different 'keys' (`id' in record definition) or having different line lengths (for fixed length structure) or different count of fields (for separated structure) for different records. Typically a `structure' maps to a file and a `records' maps to a line in the file. A structure is defined as: structure NAME { option value ... ... } A structure can contain following options: `type fixed|separated [CHAR] [*]' The fields in the input are fixed length fields or separated by CHAR. If * is defined, multiple sequential separators are considered as one. Default separator is comma. `quoted [CHAR]' Fields may be quoted with char, default quotation mark is double quotation mark '"'. A quotation mark is assumed be escaped as \CHAR or doubling the mark as CHARCHAR in input. Non escaped quotation marks are not preserved in output. `header first|all|no' Controls the occurrence of the header line. Default is no. If set as _first_ or _all_, the first line of the first input file is considered as header line containing the names of the fields. _first_ means that only the first file has a header, _all_ means means that all files have a header, all though the names are still taken from the header of the first file. Header line is handled according the record definition, meaning that the name positions, separators etc. are the same as for fields. `output NAME' All records belonging this structure are printed according output format name. Default is to use output named as `default'. `record NAME {options ...}' Defines one record for a structure. A structure can contain several record types. Record ------ A record defines one type of input line in a file. Different records can be distinguished using the `id' option or different line lengths or field counts. A record is defined as: record NAME { option value ... ... } A record can contain following options: `id POSITION STRING' Identifies a record in the input file. Records are identified by the string in input record position POSITION. For fixed length input the position is the byte position of input record and for separated input the position is the POSITION'th field of the input record. Positions start from one. A record definition can contain several id's, then all id's must match the input line (`id''s are _and-ed_). `field NAME|FILLER|* [LENGTH]|* [LOOKUP]' Defines one field in input structure. LENGTH is mandatory for fixed length input structure. Length is also used for printing the fields in fixed length format (directive `%D' in output definitions). If _*_ is defined instead of the name, then the NAME will be the ordinal number of the field, or if the `header' option has value _first_ or _all_, then the name of the field will taken from the header line (first line of the input). If field is named as `FILLER', the field will not appear in output. If LOOKUP is defined the fields contents is used to make a lookup in lookup table LOOKUP. If LENGTH is not needed (separated format) but lookup is needed, use asterisk (*) in place of length definition. The order of fields in configuration file is essential, it defines the field order in a record. `fields-from RECORD' Fields for this record are the same as for record RECORD. `field' and `fields-from' are mutually exclusive. `output NAME' This record is printed according output format NAME. Default is to use output format defined in structure. Output ------ Keyword `output' defines one output format for formatting the flat file data. Formatting is controlled using options and printf style directives. An output definition is all ways independent from structure, so one output format can be used with different input file formats. A output is defined as: output NAME { option value ... ... } Actual formatting and printing is controlled using _pictures_ in output options. Pictures can contain following printf style directives: `%f' Name of the input file. `%s' Name of the current structure. `%r' Name of the current record. `%o' Input record number in current file. `%O' Input record number starting from the first file. `%n' Field name. `%t' Field contents, without leading and trailing whitespaces. `%d' Field contents. `%D' Field contents, right padded to the field length (requires length definition for the field). `%l' Lookup value which has been found using current field as a search key. `%L' Lookup value, right padded to the field length. `%p' Fields start position in a record. For fixed structure this is field's byte position in the input line and for separated structure this is the ordinal number of the field. Starts from one. `%e' Does not print anything, causes still the "field empty" check to be performed. Can be used when only the names of non-empty fields should be printed. `%%' Percent sign. Output options: `file_header PICTURE' PICTURE is printed once before file contents. `file_trailer PICTURE' PICTURE is printed once after file contents. `header PICTURE' If defined, then the header line describing the field names is printed before records. Every field name is printed according the PICTURE using the same separator and fields length as defined for the fields. Picture can contain only `%n' directive. `data PICTURE' Field contents is printed according PICTURE. `lookup PICTURE' If current field is related to lookup table, then this PICTURE is used instead of picture from `data'. This makes possible to use different picture when the field is related to a lookup table. Default is to use the picture from `data'. `separator STRING' All fields are terminated by STRING, except the last field of the record. Default is not to print separator. `record_header PICTURE' All records are started by PICTURE. Default is not to print the record header. `record_trailer PICTURE' All records are ended with PICTURE. Default is newline. `justify left|right|CHAR' The output from the `data' option is left or right justified. CHAR justifies output according the first occurrence of CHAR in the data picture. Default is left. `indent STRING' Record contents is intended by STRING. Field contents is intended by two times the string. Default is not to indent. `field-list NAME1,NAME2,...' Only fields and constants named as NAME1,NAME2,... are printed, same effect as has option `-f'. Default is print all fields and no constants. Fields and constants are also printed in the same order as they are listed. `no-data-print yes|no' If `field-list' is defined and and this is set as no and none of the fields in `field-list' does not belong to the current record, then the `record_header' and `record_trailer' are not printed. Default is yes. `field-empty-print yes|no' When set as no, nothing is printed for fields which consist entirely of characters from `empty-chars'. If none of the fields of a record are printed, then the printing of `record_trailer' is also suppressed. Default is yes. `empty-chars STRING' STRING defines a set of characters which define an "empty" field. Default is " \f\n\r\t\v" (space, form-feed, newline, carriage return, horizontal tab and vertical tab). Lookup ------ Keyword `lookup' defines a lookup table which can searched using field contents. Found values can be printed using output directives `%l' and `%L'. A lookup table is defined as: lookup NAME { option value ... ... } Lookup options: `search exact | longest' Search method for this table. Either exact or longest match is used when searching the table. Default is `exact'. `pair KEY VALUE' Defines one key/value pair for the lookup table. `file NAME [SEPARATOR]' Data for the lookup table is read from file NAME. Each line in file NAME is considered as a key/value pair separated by a single character SEPARATOR. Default separator is semicolon. Lines without separator are silently omitted. *Note*: The file size is limited by available memory because the file contents is loaded to memory. `default-value VALUE' If searching the lookup table is unsuccessful then VALUE is used in printing. Default is empty string. Constants --------- Keyword `const' defines one name/value pair which can be used as an additional output field. Constants can be used only in field lists (option `-f,--field-list', or output option `field-list'). Constants can be used to add fields to output which do not appear in input. E.g. new fields for separated output or adding spaces after a fixed length field (changing the field length). Note that VALUE is printed as it is for every record. It cannot be changed record by record. If a constant has the same name as one of the input fields, the value VALUE is printed instead of the input field contents. A constant is defined as: const NAME VALUE When NAME appears in field list it is treated as one of the input fields having contents VALUE.  File: ffe.info, Node: Guessing, Next: Limits, Prev: Configuration, Up: Invoking ffe 3.3 Guessing ============ If `-s' is not given, `ffe' tries to guess the input structure. `ffe' reads first 10 000 lines or 1 MB of input data and tries to match the structure definitions from configuration file to input stream. If all lines match one and only one structure, the structure is used for reading the input file. Guessing uses following execution cycle: 1. Input line is read 2. All record `id''s are compared to the input line, if all `id''s of a record match the input line and the records line length matches the total length (or total count for separated structure) of the fields, the record is considered to match the input line. If there are no `id''s, only the line length or field count is checked. 3. If all lines match at least one of the records in a particular structure, the structure is considered as selected. There must be only one structure matching all lines used for guessing.  File: ffe.info, Node: Limits, Prev: Guessing, Up: Invoking ffe 3.4 Limitations =============== At least in GNU/Linux `ffe' should be able to handle big files (> 4 GB), other systems are not tested. Regular expression can be used in expressions (operator *?* in option `-e', `--expression') only in systems where regular expression functions (regcomp, regexec, ...) are available.  File: ffe.info, Node: ffe configuration, Next: Problems, Prev: Invoking ffe, Up: Top 4 How `ffe' works ***************** Following examples use two different input files: Fixed length example -------------------- Fixed length personnel file with header and trailer, line (record) is identified by the first byte (H = Header, E = Employee, B = Boss, T = trailer). $cat personnel.fix H2006-02-25 EJohn Ripper 23 BScott Tiger 45 EMary Moore 41 ERidge Forrester 31 T0004 $ Structure for reading file above. Note that record `boss' reuses fields from `employee'. structure personel_fix { type fixed record header { id 1 H field type 1 field date 10 } record employee { id 1 E field EmpType 1 field FirstName 9 field LastName 13 field Age 2 } record boss { id 1 B fields-from employee } record trailer { id 1 T field type 1 field count 4 } } Separated example ----------------- Same file as above, but now separated by colon. $cat personnel.sep H,2006-02-25 E,john,Ripper,23 B,Scott,Tiger,45 E,Mary,Moore,41 E,Ridge,Forrester,31 T,0004 $ Structure for reading file above. Note that the field lengths are not needed in separated format. structure personel_sep { type separated , record header { id 1 H field type field date } record employee { id 1 E field type field FirstName field LastName field Age } record boss { id 1 B fields-from employee } record trailer { id 1 T field type field count } } Printing in XML format ---------------------- Data in examples above can be printed in XML using output definition like: output xml { file_header "\n" data "<%n>%t\n" record_header "<%r>\n" record_trailer "\n" indent " " } Example output using command (assuming definitions above are saved in ~/.fferc) `ffe -p xml personnel.sep'
H 2006-02-25
E john Ripper 23 B Scott Tiger 45 E Mary Moore 41 E Ridge Forrester 31 T 0004 Printing sql commands --------------------- Data in examples above can be loaded to database by generated sql commands. Note that the header and trailer are not loaded, because only fields `FirstName',`LastName' and `Age' are printed and `no-data-print' is set as no. This prevents the `record_header' and `record_trailer' to be printed for file header and trailer. output sql { file_header "delete table boss;\ndelete table employee;\n" record_header "insert into %r values(" data "'%t'" separator "," record_trailer ");\n" file_trailer "commit\nquit\n" no-data-print no field-list FirstName,LastName,Age } Output from command `ffe -p sql personnel.sep' delete table boss; delete table employee; insert into employee values('john','Ripper','23'); insert into boss values('Scott','Tiger','45'); insert into employee values('Mary','Moore','41'); insert into employee values('Ridge','Forrester','31'); commit quit Human readable output --------------------- This output format shows the fields suitable for displaying in screen or printing. output nice { record_header "%s - %r - %f - %o\n" data "%n=%t\n" justify = indent " " } Output from command `ffe -p nice personnel.fix' personel - header - personnel.fix - 1 type=H date=2006-02-25 personel - employee - personnel.fix - 2 EmpType=E FirstName=John LastName=Ripper Age=23 personel - boss - personnel.fix - 3 EmpType=B FirstName=Scott LastName=Tiger Age=45 personel - employee - personnel.fix - 4 EmpType=E FirstName=Mary LastName=Moore Age=41 personel - employee - personnel.fix - 5 EmpType=E FirstName=Ridge LastName=Forrester Age=31 personel - trailer - personnel.fix - 6 type=T count=0004 HTML table ---------- Personnel data can be displayed as HTML table using output like: output html { file_header "\n\n\n\n\n\n" header "\n" record_header "\n" data "\n" file_trailer "
%n
%t
\n\n\n" no-data-print no } Output from command `ffe -p html -f FirstName,LastName,Age personnel.fix'
FirstName LastName Age
John Ripper 23
Scott Tiger 45
Mary Moore 41
Ridge Forrester 31
Using expression ---------------- Printing only Scott's record using expression with previous example: `ffe -p html -f FirstName,LastName,Age -e FirstName^Scott personnel.fix'
FirstName LastName Age
Scott Tiger 45
Using replace ------------- Make all bosses and write a new personnel file printing the fields in fixed length format using directive `%D': Output definition: output fixed { data "%D" } Write a new file: $ffe -p fixed -r EmpType=B -o personnel.fix.new personnel.fix $cat personnel.fix.new H2006-02-25 BJohn Ripper 23 BScott Tiger 45 BMary Moore 41 BRidge Forrester 31 T0004 $ Using constant -------------- The length of the fields FirstName and LastName in fixed length format will be made two bytes longer. This will be done by printing a constant after those two fields. We use dots instead of spaces in order to make change more visible. Because we do not want to change header and trailer we need specially crafted configuration file. Employee and boss records will be printed using new output FIXED2 and other records will be printed using output DEFAULT. New definition file `new_fixed.rc': const 2dots ".." structure personel_fix { type fixed record header { id 1 H field type 1 field date 10 } record employee { id 1 E field EmpType 1 field FirstName 9 field LastName 13 field Age 2 output fixed2 } record boss { id 1 B fields-from employee output fixed2 } record trailer { id 1 T field type 1 field count 4 } } output default { data "%D" } output fixed2 { data "%D" field-list Emptype,FirstName,2dots,LastName,2dots,Age } Print new flat file: $ ffe -c new_fixed.rc personel_fix H2006-02-25 EJohn ..Ripper ..23 BScott ..Tiger ..45 EMary ..Moore ..41 ERidge ..Forrester ..31 T0004 $ Using lookup table ------------------ Lookup table is used to explain the EmpTypes contents in output format `nice': Lookup definition: lookup Type { search exact pair H Header pair B "He is a Boss!" pair E "Not a Boss!" pair T Trailer default-value "Unknown record type!" } Mapping the EmpType field to lookup: structure personel_fix { type fixed record header { id 1 H field type 1 field date 10 } record employee { id 1 E field EmpType 1 Type field FirstName 9 field LastName 13 field Age 2 } record boss { id 1 B fields-from employee } record trailer { id 1 T field type 1 field count 4 } } Adding the lookup option to output definition `nice'. output nice { record_header "%s - %r - %f - %o\n" data "%n=%t\n" lookup "%n=%t (%l)\n" justify = indent " " } Running ffe: $ffe -p nice personnel.fix personel_fix - header - personel_fix - 1 type=H date=2006-02-25 personel_fix - employee - personel_fix - 2 EmpType=E (Not a Boss!) FirstName=John LastName=Ripper Age=23 personel_fix - boss - personel_fix - 3 EmpType=B (He is a Boss!) FirstName=Scott LastName=Tiger Age=45 personel_fix - employee - personel_fix - 4 EmpType=E (Not a Boss!) FirstName=Mary LastName=Moore Age=41 personel_fix - employee - personel_fix - 5 EmpType=E (Not a Boss!) FirstName=Ridge LastName=Forrester Age=31 personel_fix - trailer - personel_fix - 6 type=T count=0004 External lookup file -------------------- In previous example the lookup data could be read from external file like: $cat lookupdata H;Header B;He is a Boss! E;Not a Boss! T;Trailer $ Lookup definition using file above: lookup Type { search exact file lookupdata default-value "Unknown record type!" } The whole configuration file used in examples --------------------------------------------- structure personel_fix { type fixed record header { id 1 H field type 1 field date 10 } record employee { id 1 E field EmpType 1 Type field FirstName 9 field LastName 13 field Age 2 } record boss { id 1 B fields-from employee } record trailer { id 1 T field type 1 field count 4 } } structure personel_sep { type separated , record header { id 1 H field type field date } record employee { id 1 E field type field FirstName field LastName field Age } record boss { id 1 B fields-from employee } record trailer { id 1 T field type field count } } output xml { file_header "\n" data "<%n>%t\n" record_header "<%r>\n" record_trailer "\n" indent " " } output sql { file_header "delete table boss;\ndelete table employee;\n" record_header "insert into %r values(" data "'%t'" separator "," record_trailer ");\n" file_trailer "commit\nquit\n" no-data-print no field-list FirstName,LastName,Age } output nice { record_header "%s - %r - %f - %o\n" data "%n=%t\n" lookup "%n=%t (%l)\n" justify = indent " " } output html { file_header "\n\n\n\n\n\n" header "\n" record_header "\n" data "\n" file_trailer "
%n
%t
\n\n\n" no-data-print no } output fixed { data "%D" } lookup Type { search exact pair H Header pair B "He is a Boss!" pair E "Not a Boss!" pair T Trailer default-value "Unknown record type!" } Using `ffe' to test file integrity ---------------------------------- `ffe' can be used to check flat file integrity, because `ffe' checks for all lines the line length and id's for fixed length structure and field count and id's for separated structure. Integrity can be checked using command `ffe -p no -l inputfiles...' Because option `-p' has value `no' nothing is printed to output except the error messages. Option `-l' causes all erroneous lines to be reported, not just the first one. Example output: ffe: Invalid input line in file 'inputfileB', line 14550 ffe: Invalid input line in file 'inputfileD', line 12  File: ffe.info, Node: Problems, Prev: ffe configuration, Up: Top 5 Reporting Bugs **************** If you find a bug in `ffe', please send electronic mail to . Include the version number, which you can find by running `ffe --version'. Also include in your message the output that the program produced and the output you expected. If you have other questions, comments or suggestions about `ffe', contact the author via electronic mail to . The author will try to help you out, although he may not have time to fix your problems.  Tag Table: Node: Top900 Node: Overview1960 Node: Samples2600 Node: Invoking ffe4089 Node: Invocation4722 Node: Configuration7857 Node: Guessing19120 Node: Limits20164 Node: ffe configuration20557 Node: Problems34696  End Tag Table